|Tenure|Coach|Years|Record|Pct.|
|---|---|---|---|---|
|1892|Shelby Fletcher|1|1–0|1.000|
|1893|W. M. Walker|1|4–6–1|.409|
|1894|J. H. Lyons|1|10–3|.769|
|1895|J. F. Jenkins|1|9–3|.750|
|1896|Eli Abbott|1|5–5|.500|
|1897|"Kid" Peeples|1|10–0|1.000|
|1898|Joseph Black|1|2–3|.400|
|1899|F. C. Owen|1|3–6|.333|
|1900|Ardis Smith|1|9–3|.750|
|1901–1905|Thomas Stouch|5|49–25–1|.660|
|1906|Schwartz|1|4–16–1|.214|
|1907–1910|J. W. H. Pollard|4|66–22–1|.747|
|1911|Guy Lowman|1|12–5|.706|
|1912–1915|D. V. Graves|4|66–30–1|.686|
|1916–1919|B. L. Noojin|4|55–18|.753|
|1920|Gordon W. Lewis|1|15–2|.882|
|1921–1923|Charles Bernier|3|28–35–4|.448|
|1924–1927|Wallace Wade|4|61–32–2|.653|
|1928|Hank Crisp|1|12–7–2|.619|
|1929–1930|Jess Neely|2|28–15–2|.644|
|1931–1932|Sam Hinton|2|23–7–2|.750|
|1933–1934|Jennings B. Whitworth|2|21–11|.656|
|1943|Paul Burnham|1|12–6|.667|
|1946|Dixie Howell|1|13–7|.650|
|1935–1942 1947–1963|Tilden Campbell|25|355–168–4|.677|
|1964–1969|Joe Sewell|6|106–79|.573|
|1970–1979|Hayden Riley|10|236–206–1|.533|
|1980–1994|Barry Shollenberger|15|487–334–1|.593|
|1995–2009|Jim Wells|15|625–322|.656|
|2010–present|Mitch Gaspard|4|133–115|.536|
|Totals|30 coaches|121 seasons|2,461–1,490–23|.623|

Question: what was the average number of years served by a coach?
Answer: 4